Half-way through ingress by most estimates, but epsilon Aurigae continues to confound. Middle of October, the star changed its rate of decline in brightness, from rapid to less rapid - see the visual light curve data link. This change of slope seems to be more pronounced at shorter wavelengths, less pronounced at longer wavelengths. Clues like these will help us define the nature of the eclipsing body more precisely. If purely due to effective area, it says that the disk is slightly thinner-looking in bluer light, relative to red wavelengths. Ultraviolet light curves during last eclipse seem consistent with this trend.Read more
Hello Citizen Skyers!
It has been a while, so I thought I’d update everyone on a few components of the Citizen Sky Project...
The eclipse is now well underway and Dr. Bob has been doing a great job keeping us updated on all of the "ins and outs" of the decline. If you haven't already, read Dr. Bob's blog posts for the latest on the eclipse! Read more
The chat transcript to our Nov. 18 online Beginner's Chat has been posted. The chat was for those Citizen Sky participants who are relatively new to astronomy and/or the Citizen Sky project. Below is the original announcement:
Everyone is invited to an online "Beginners' Chat" to be held this Wednesday, November 18 at 8 pm Eastern (7 pm Central, 6 pm Mountain, 5 pm Pacific). The goal of the chat is to answer questions about Citizen Sky, epsilon Aurigae, and/or astronomy in general. The tone will be tailored to new participants in the project so this is a great chance to find out more about the project without feeling overwhelmed by the scale of the project.Read more
Mid-November, ingress nominally 2/3 over, and the snows are arriving in the mountains. We made one last attempt to reach Mt.Evans observatory on 14 Nov but huge drifts defeated the stout Unimog vehicles we used. However, intrepid observers elsewhere are still getting peeks at the star, sometimes between clouds. Some interesting trends are emerging since mid-October: the B filter photometry shows a decreased rate of decline, as does V filter (less so), but R and I filters appear to continue the decline in a linear fashion. This means the star is relatively brighter in bluer wavelengths compared to redder ones - suggesting a hotter source - perhaps the F star pulsations continuing (like those seen pre-eclipse) and/or some of the supposed hot B star light is leaking out of the dark disk. Richard Miles reports an ~0.1 mag jump in V-Ic after mid-Oct.Read more
Greetings again from historic Mount Wilson Observatory, perched in the Angeles National Forest mountains, above Los Angeles. As previously mentioned, we're here using the Center for High Angular Resolution Astronomy (CHARA) telescope array of 6 one-meter telescopes, operated by Georgia State University. The light from 4 of these telescopes at a time can be merged in the Michigan IR Combiner, or MIRC. Each pair of telescopes is capable of producing interference fringes. Measuring the fringe contrast and knowing the wavelength and telescope separation for each pair over the course of an evening, provides pieces of information that can be used to construct an image.Read more